/** Copyright (c) 2008-2009, Markos Evlogimenos
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * The name of Markos Evlogimenos may be used to endorse or
 *		 promote products derived from this software without specific
 *		 prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */

package org.kamimark.collections;

import java.util.Iterator;
import java.util.NoSuchElementException;

public abstract class AbstractXDArray<T> implements Iterable<T>
{

	private class XDArrayIterator<Z> implements Iterator<Z>
	{

		private final Z[] array;
		int index;

		public XDArrayIterator(final Z[] array) {
			this.array = array;
		}

		public boolean hasNext() {
			return index < array.length;
		}

		public Z next() throws NoSuchElementException {
			if (!hasNext())
				throw new NoSuchElementException();
			return array[index];
		}

		public void remove() {
			throw new UnsupportedOperationException();
		}

	}

	private static final long serialVersionUID = 1L;
	protected final T[] array;

	protected final int[] dimensionSizes;

	@SuppressWarnings("unchecked")
	protected AbstractXDArray(final int... dimensionSizes) {
		this.dimensionSizes = dimensionSizes;

		int totalSize = 0;
		for (final int size : dimensionSizes)
			totalSize *= size;
		array = (T[]) new Object[totalSize];
	}

	protected boolean checkDimensionsValidity(final int[] dimensions) {
		return dimensions.length == dimensionSizes.length;
	}

	protected int findPosition(final int[] dimensions) {
		int pos = dimensions[0];
		for (int i = 1; i < dimensionSizes.length - 1; i++)
			pos += dimensions[i] * dimensionSizes[i - 1];
		return pos;
	}

	protected T getT(final int... dimensions) {
		final int pos = findPosition(dimensions);
		return array[pos];
	}

	public Iterator<T> iterator() {
		return new XDArrayIterator<T>(array);
	}

	protected T setT(final T element, final int... dimensions) {
		int pos = dimensions[0];
		for (int i = 1; i < dimensionSizes.length - 1; i++)
			pos += dimensions[i] * dimensionSizes[i - 1];
		final T old = array[pos];
		array[pos] = element;
		return old;
	}
}
